Means for producing electric oscillations by an electric arc



Jul 29, 1924. I

' R. HERZOG MEI KNS FOR PRODUCING ELECTRIC OSCILLATiONS BY AN ELECTRIC ARC Filed July 12 1920 Hal l/VVENTQE Passer HEPZOG AI'TOENE Y5 Patented July 29, 1924 7 ROBERT HERZOG, OF BERLIN, GERMANY, ASSIGNOR TO C. LORENZ AKTIENG-ESELL- SGHAFT, OF LORENSWEG-BERLIN TEMPE-LHOF, GERMANY.

MEANS roR raonUCnve ELECTRIC osoiLLarloivs BY AN ELECTRIC ARC.

Application filed July 12,1920. Serial No. 395,810.

To all whom it may concern:

Be it known that I, ROBERT Hnazoe, residing at Berlin, Germany, have invented certain new and useful Improvements in Means for Producing Electric Oscillations by an Electric Arc, for which I have filed appli- Cations in Germany, June 5, 1918; Holland, Aug. .8, 1919'; Denmark, Aug. 9, 1919; Norway, Aug. 18, 1919; Sweden, Aug. 28, 1919; England, Sept. 16, 1919; and in France, Oct. 14, 1919, of which the following is a specification. i

In the method of producing oscillations by means of the electric arc irregularities in the burning of the electric are often occur because it is practically impossible to keep the conditions to which the arc is subjected completely constant and small diiferences in the substance of the electrodes are sufficient to 1 cause changes of wave length. Although these changes are so small that the fluctuations of energy arenot noticeable whilst receiving they are nevertheless exceedingly troublesome because in receiving waves with surging amplitudes the changes of wave lengths result in variations of the tone pitch and, instead of a simple tone, a twittering note results because in the measure in which the wave length changes, trains of higl'ier and lower tones arise in alternate succession.

This invention relates to a method of 0btaining an extraordinarily uniform burning of the electric arc with the aid of a self-induction, this self-induction being connected in series with the arc and made very large. A capacity whose magnitude liesoutside the range of the tuning must evidently be inserted in a circuit comprising the light are and the two self-induction coils, in order to avoid short-circuitingof the continuous current. Another result obtained by this methodconsists in an appreciable increase of the efficiency of the light arcs now employed.

The invention is illustrated in the drawing in which Figure 1 shows a form of circuitv ema Figure 2illustrates'a circuit inwhich .a Qup ng 0f the sel -induction withia'erial is avoided and m- 1.;

Figures 3 and 4 show tions of the circuit. 1

A self-induction s, Figure 1, of compara-. tively largesize isconnected in series with the electric arc 8 v and an electromagnetic field ofsimilar magnitude is, connected in parallel, to the self-induction -8 and the arc; In order to avoid short-circuiting of the con tin'uous current a capacity 0 is further provided whose magnitude does not influence the oscillation and is consequently not critical beyond a determined value. With all currents which flow parallel through these selfinductions s and 8 the total self induction is reduced and it can be reduced to a very small figure if the two fields are intimately coupled with each other. For all currents, which pass through the two self-inductions in series the full value of. these self-inductions comes however in question.

The result of this arrangement is that, within very wide limits, the extinguishing or even the irregular burning of the arc is prevented because as soon as the fields in the two branch paths become unequal a high tension of the self-induction immediately arises at the electric arc'and renders harmless any resistance which may be offered by the are. It is therefore possible to adapt without any difiiculty the light arc to such a gap between the electrodes that a much higher value of current is obtained in the oscillating system (antenna A) than the continuous current supplied, so that the eiii-, ciency is increased to a multiple of that attained in the type of Circuit hitherto employed. The independence of the arc is so marked that it is possible to change the polarity of the continuous current at the electrodes without any deleterious effect.

An essential feature of the invention is that directlyat the high frequency side of thelight arc liesa self-induction, which is as I large as possible, for the purpose of governing the arc. But this large self-induction 8 shall enter into action only when irregularities occur in the arc and it shall be as ineffective .as possible when the oscillations passing in. the antenna circuit are regular-so as -myeaable Wa es at 'eemp a ely y further modificathe light arc, a circuit which does not osciltenna circuit is entirely or nearly neu- 10 late independently situated on the high fretralized.

quency side of said light are between the are In testimony whereof I have signed this and the oscillating circuit, a large selfspecification in the presence of two witnesses.

, inductance in said circuit, and a second self inductance connected in parallel with said ROBERT HERZOG. first self inductance and said light arc in lVitnesses: such a manner that the efiect of said first MAX JAKowsKl,

self inductance upon the oscillatory an- FRITZ MARXLAUER. 

